Various prior art devices have been developed to perform surface finishing operations such as sanding, grinding, buffing, polishing and stropping. Examples of such devices are disclosed in U.S. Pat. Nos. 2,175,073, 2,316,161, 2,690,632, 3,250,045, 3,844,072, 4,837,985, and 4,951,423. With the exception of the '985 patent issued to Mayama which shows a cylindrical abrasive member, all the rest of the patents listed above show various disc shaped members which are attached to one end of a spindle and which lie in a plane which is substantially perpendicular to the spindle. The discs may have finishing textures or surfaces suitable for sanding, polishing or other finishing operations and the finishing textures or surfaces may be on one or both sides of such disc members. When there are finishing surfaces on both sides of the disc member, the member can be attached to the end of the spindle with either side facing away from the end of the spindle to perform the finishing operation. Then, when one side of the disc is worn the disc can be removed from the spindle and replaced with the unworn side facing away from the end of the spindle in a direction to perform the finishing operation. When discs are mounted on the end of a spindle in a plane perpendicular to the spindle, the disc rotates in a circumferential direction when the spindle is rotated and the finishing surface of the disc engages the surface to be finished in a circular motion. In some instances this can leave a circular or swirling pattern on the surface being finished. The present invention contacts the surface being finished in a linear sweeping motion quite similar to that of a belt sander and therefore does not leave any circular or swirling pattern on the finished surface.
The disc members in the above patents are designed for finishing a flat surface or gradually curving surfaces but are not capable of finishing the inside of holes or irregular surfaces with small radius curves. The present invention as hereinafter described, is capable of finishing the surfaces of both flat and curved surfaces as well as the inside of holes.